# HW7 - ECE 473/TAM 413 Homework Assignment#7 Due Friday 1 A...

This preview shows pages 1–2. Sign up to view the full content.

ECE 473/TAM 413 Homework Assignment #7 Due: Friday, October 24, 2008 1. A pulsating sphere of radius a = 0.15 m radiates spherical waves into air at a frequency of 100 Hz. (a) The intensity at a distance of 0.5 m from the center of the spherical source is 10 W/m 2 . Determine the total acoustic power passing through the surface of a sphere of radius 0.5 m centered on the spherical source. (b) At the surface of the sphere, r = a, compute the intensity and the amplitudes of the acoustic pressure and particle velocity. 2. Consider a simple monopole source radiating into free space (something like a loudspeaker high above a football stadium rather than in a living room). In order to produce sound of frequency 1000 Hz and level SPL = 100 dB at a distance of 15 m, (a) what must be the source strength Q (rms), (b) what must be the intensity and (c) what must be the total acoustic power radiated? Assume it is a nice sunny day at 20˚C. 3. A 0.2-m-radius hemispherical sound source is mounted near to a rigid plane boundary and

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 09/19/2009 for the course ECE 473 taught by Professor Obrian during the Fall '08 term at University of Illinois at Urbana–Champaign.

### Page1 / 2

HW7 - ECE 473/TAM 413 Homework Assignment#7 Due Friday 1 A...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online